In an electrical system, there are many integrated circuit (IC) chips arranged in one or more IC packages or electrical devices, such as a memory, an analog-to-digital converter, wireless communication devices, or an application processor, in a chip. In some applications, data communication among different IC chips and/or different electrical devices are performed based on one or more communication protocols, such as Serial Peripheral Interface (SPI) protocol or Inter-Integrated Circuit (I2C) protocol. As bandwidth requirement of the data communication among different IC chips and/or different electrical devices increases, various data communication protocols having a data rate faster than those of SPI or I2C are being developed.